The chelicerae no longer appear to spring from an independent postoral segment.
Dorsally the heart is now very conspicuous, and in front of the chelicerae may be seen the supra-oesophageal ganglia.
There are four joints in the pedipalpi, while the chelicerae do not exhibit any signs of becoming jointed till somewhat later.
The chelicerae are two-jointed, and terminate in what appear like rudimentary chelae, a fact which perhaps indicates that the spiders are descended from ancestors with chelate chelicerae.
There is a distinct ganglionic thickening for thechelicerae quite independent of the procephalic lobes.
On each side of and behind the mouth two whitish masses are visible, which are the epiblastic thickenings which constitute the ganglia of the chelicerae (Pl.
Balbiani believes that the segment of the chelicerae is formed later than that of the six succeeding segments.
Ventral view with the prosomatic appendages cut short excepting the chelicerae (i) whose sharp retroverts are seen.
When the scorpion has paralysed its prey in this way, the two short chelicerae are brought into play (fig.
The position of the chelicerae of Limulus and of the ganglionic nerve-masses from which they receive their nerve-supply, is closely similar to that of the same structures in Scorpio.
The coxae of the five pairs of limbs following the chelicerae were arranged in a series on each side between the mouth, M, and the metasternites, mets.
Of these appendages the chelicerae and endognaths tend to dwindle away and become mere tentacles, while the large swimming ectognath and metastoma remain strong and vigorous.
Gerhard Holm, however, in his recent beautiful preparations from Schmidt's specimens and others collected at Rootzikuell, has proved most conclusively that the chelicerae of Eurypterus were of the same kind as those of Limulus.
There seems to be some doubt about the homology of the pedipalps with the mandibles, as at least one investigator claims to have found rudiments of a segment between the one bearing the chelicerae and that with the pedipalps.
At the time these buds appear, the chelicerae are post-oral, but afterward move forward so that both rostrum and chelicerae are in front of the mouth.
The rostrum is therefore the product of the union of the antennules, and the chelicerae are to be homologized with the antennae.
Thus arise the chelicerae of most arachnids, and the two pairs of tactile antennae of most Crustacea.
Chelicerae are not known, and pleural lobes are well developed in this group.
On the germ band there appear a pair of buds in front of the rudiments of the chelicerae which later unite to form the rostrum of the adult.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "chelicerae" in a variety of sentences. We hope that you will now be able to make sentences using this word.
